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Topic: Geared stepper motor (Read 985 times)

I am building a Cartesian robot (X,Y,Z) and will be using two stepper motors for the X and Y axis to rotate the ballscrew. If I go for a geared stepper motor will it be a good idea? I was thinking of something similar to this one:

Gear reducing a stepper increases the output torque and decreases the maximum speed (RPM).Is this what you need?

The driver is just barely enough (look at the Max current rating of the motor and driver) for that motor.It might require forced air cooling as per the instructions.It also depends on how hard to work the motor (mechanical loading), how fast you try the run the motor and at what Voltage you feed the driver.

Gearing on a stepper motor will give you more torque, slower speed, higher losses, and higher play/backlash.If it's worth it to you depends on your requirements. It may be better to use a larger stepper motor, or a finer-pitch screw, or both, instead of a gearbox.

The stepper motor you link to is rated 12V and 1.6A; the driver you link to is rated 8-45V and 1.5A (up to 2.2A peak if you add heatsinks.)So if you add heatsinks, and don't exceed 12V (so the stepper doesn't draw more,) then that driver may work.

Neither of them is great for what you want -- specifically, all of them will only actually deliver the rated currents with additional cooling (adding a heat sink.)If I had to choose between those, I would probably get the 8825 and add an aluminum heat sink to the chip with some thermal glue.If I wanted something robust, I would go with a bigger driver.

That device does have the heat sinking, but it doesn't say whether 3.5A is "per coil" or "in total."However, it does look more robust than the Pololu bare boards, given that it has the heat sinking already integrated.